Marcos Ambrose won a thrilling, physical battle with Brad Keselowski and Kyle Busch on the final lap Sunday to win for the second consecutive year at Watkins Glen International.

Kyle Busch took the white flag as the leader but with his car slipping and sliding in oil that had leaked onto the track, Keselowski quickly ran him down and hit Busch’s car, spinning him out.

Ambrose then chased down Keselowski and bumped him, charging into the lead. Ambrose and Keselowski bumped multiple times as they raced to the checkered flag. They went into the final turn bumping and banging and side by side, but Ambrose pulled ahead and held on for the win.

Keselowski, who led 37 laps, said he accidentally spun Busch because Busch’s was slipping and sliding in oil that had leaked onto the track. Other drivers also complained about the slick track, which had oil on it from Bobby Labonte's smoking car.

“There was nothing I could do,” Keselowski said. “There was one big giant oil slick under his car.

Dale Earnhardt Jr. wrecked with seven laps to go and finished 28th, relinquishing the Sprint Cup points lead to Johnson, who finished third.

Ambrose moved into contention for a Chase wild-card spot with his first win of the season. Kasey Kahne leads the wild-card standings with two wins while Ambrose, Busch, Jeff Gordon, Ryan Newman and Joey Logano each have one victory.

The two drivers between 11th and 20th in the standings with the most wins make the Chase. With four races remaining before the Chase, Kahne leads the wild-card standings followed by Newman, Busch, Gordon, Ambrose and Logano.

Earnhardt, meanwhile, fell four spots in the standings. Johnson leads Greg Biffle by one point and Matt Kenseth by two. Earnhardt, who had led the standings the after the past two races, is 17 points back in fourth.

"I just made a mistake overdriving the car," said Earnhardt, one of several drivers to complain about oil on the track late in the race.

Gordon slid in oil and wrecked on the final lap, finishing 21st.

"Those last two laps were out of control with oil on the track," Johnson said. "Guys were spinning all over the place. It was chaos."

"The track shouldn't have oil all over it," Earnhardt said.

Busch led a race-high 43 laps and regained the lead with a bold move on a restart with 16 laps to go. Keselowski held the lead, but Busch charged by him on the inside and Ambrose on the outside. Busch then swung wide over the rumble strips coming out of Turn 1 and held off Ambrose to take the lead. He appeared to be in control until he began slipping and slowing on the final lap.

That's when the fireworks erupted.

"It was just great racing," Ambrose said. "That's the way racing should be."

Ambrose's victory was the second of his career, both at Watkins Glen.

"It feels so good," Ambrose said. "Last year's was just relief, this is just pure joy. A great day."

Pole-sitter Juan Pablo Montoya was among several drivers who had early problems. Montoya was running in the top five after the first round of pit stops when a control arm on his car broke, sending him to the garage. He finished 33rd.

“We had a car to win today. It was looking really good and everything was going according to plan, and then I hit a curb and all of a sudden it wouldn’t turn,” Montoya said.

Teammate Jamie McMurray, Kurt Busch and Joey Logano also had mechanical failure early in the race. McMurray and Busch both wrecked, with Busch’s left front wheel coming off the car.